Additional Study Information: A prospective, multicenter single-arm, open label study to evaluate the safety and effectiveness of the Neuroguard IEP System for the treatment of carotid artery stenosis in subjects at elevated risk for adverse events following carotid endarterectomy (CEA). The Neuroguard IEP System is a 3-in-1 carotid stent delivery system consisting of an angioplasty balloon, an integrated embolic protection device and a nitinol self-expanding stent loaded over the balloon and constrained by an outer sheath. Eligible patients between 20 and 80 years of age have been diagnosed with either de-novo atherosclerotic or post CEA restenotic lesion(s) in the internal carotid arteries (ICA) or at the carotid bifurcation with 50% stenosis if symptomatic or 80% stenosis if asymptomatic (both defined by angiography using NASCET methodology). Symptomatic patients are defined as having stroke or TIA ipsilateral to the carotid lesion within 180 days of the procedure within the hemisphere supplied by the target vessel. Enrolled subjects will be followed at 30 days, 6 months, 12 months, 24 months and 36 months.